The present invention relates to methods for obtaining metal hollow ingots by electroslag remelting, and to devices for effecting same. The invention may be made use of for obtaining hollow ingots of pipe stock from steels, alloys and metals (ball-bearing, highly alloyed, heat-resistant, anticorrosive, high-strength structural, and the like including those difficult to work), intended for being subsequently processed into pipes and other articles by pressing, rolling out, rolling, etc.
Known in the prior art is a method for obtaining hollow metal ingots by the electroslag remelting of a hollow (in the tubular form) consumable electrode in a cooled annular ingot mold composed of a cooled mold and a cooled bottom plate together with a cooled core being made stationary in relation therewith.
In this case, a consumable electrode is remelted in an annular gap between the mold and core. During the entire remelting process of a hollow ingot, the slag bath is given an annular form. Its cross section is almost equal to that of a hollow ingot to be made.
A disadvantage of the prior-art method consists first of all in that for making ingots there are employed expensive hollow (in the tubular form) consumable electrodes. Moreover, the hollow ingot to be built-up squeezes the core during shrinkage, which may cause cracking in the ingot, and as a result the core will have to be removed from each ingot by mechanical means.
The primary object of the present invention is to provide apparatus using electroslag remelting to make ingots which would permit using cheap consumable electrodes of a solid section (both deformed or cast), precluding the formation of cracks in the ingot, and features, according to the invention, a mold, a consumable metal electrode and a bottom plate upon which an ingot is secured on in the process of remelting the consumable electrode, the mold and bottom plate can have longitudinal motion relative to each other during remelting, axial movement of the electrode is provided and a source of electric power connects the consumable electrode and bottom plate and electrical leads connect both the mold and the bottom plate to the same potential.
The nature of the present invention will further be made more fully apparent from a consideration of the following description of its exemplary embodiments, taken in conjunction with the accompanying drawing.